# Co-occurrence of autism and ADHD > Developing situation record from CLSTR: https://clstr.news/situations/co-occurrence-of-autism-and-adhd > Updated: 2026-11-06T10:00:23.000Z. Sources: 26. Developments: 5. Research and clinical observations highlight the significant overlap between autism spectrum disorder and attention deficit hyperactivity disorder, a combination colloquially known as “AuDHS” or “AuDHD”. Experts note that these conditions can create conflicting needs, such as the autistic requirement for routine and quiet versus the ADHD need for stimulation and novelty. This interaction has been described by psychotherapist Sascha Reiners as a potential “fire and ice” phenomenon, which can lead to sensory overload and executive function challenges. Medical data indicates a high rate of comorbidity, with some studies suggesting that 50% to 70% of individuals with autism also have ADHD, while meta-analyses suggest a range of 28% to 38.5%. Recent clinical shifts, such as the transition from DSM-IV to DSM-5, now allow for dual diagnoses. In Italy, local health authorities like Asl 1 in L'Aquila are emphasizing synergy between schools, families, and healthcare to manage a reported 63% increase in ADHD diagnoses between January and September. Research underscores strong familial links. A 2024 study in JAMA Psychiatry supports high heritability for autism and a higher occurrence of ADHD among relatives. Neurologist Dr. Matheus Trilico notes that parents frequently recognize similar behavioral patterns in themselves following a child’s diagnosis. Furthermore, Dr. Pablo Agüero Rabes warns that ADHD often goes undiagnosed in adults who rely on compensation strategies until increased demands make struggles with organization and impulsivity more apparent. A study at University Hospitals in Cleveland involving 81 children found that many receive autism diagnoses only after being identified with other conditions: 54% had prior ADHD diagnoses and 36% had prior anxiety diagnoses. ## Timeline ### 2026-11-06: ADHD and autism diagnosis trends in Italy Increased clinical awareness in Italy is revealing high rates of co-occurring ADHD and autism, prompting calls for better collaboration between schools, families, and health services. 3 sources. https://clstr.news/cluster/adhd-and-autism-diagnosis-trends-in-italy ### 2026-11-05: Study reveals high prevalence of ADHD and anxiety in children diagnosed with autism A study of school-aged children shows that over half of those diagnosed with autism had previously been diagnosed with ADHD, while over a third had an existing anxiety diagnosis. 5 sources. https://clstr.news/cluster/study-reveals-high-prevalence-of-adhd-and-anxiety-in-children-diagnosed-with-autism ### 2026-11-04: Medical experts discuss links between ADHD, autism, and family history Medical experts discuss the genetic links between autism and ADHD, noting that many adults live for decades with undiagnosed ADHD symptoms. 5 sources. https://clstr.news/cluster/medical-experts-discuss-links-between-adhd-autism-and-family-history ### 2026-10-29: Neurodivergence research highlights co-occurrence of autism and ADHD Medical experts highlight the rising recognition of “AuDHD”, the co-occurrence of autism and ADHD, noting that many individuals experience overlapping and sometimes contradictory neurodivergent traits. 2 sources. https://clstr.news/cluster/neurodivergence-research-highlights-co-occurrence-of-autism-and-adhd ### 2026-10-23: AuDHS: The coexistence of ADHD and Autism AuDHS refers to the simultaneous occurrence of ADHD and autism, where the two conditions can mask or intensify each other's symptoms. 11 sources. https://clstr.news/cluster/audhs-the-coexistence-of-adhd-and-autism --- Cite as: Co-occurrence of autism and ADHD. CLSTR, https://clstr.news/situations/co-occurrence-of-autism-and-adhd